Lapping machine



1 June 15, 1937. H. s. INDGE LAPPING MACHINE Filed May 14, 1956 2 Sheets-Sheet l 3 Mam bo a HERBERT Si INDGE June 15, 1937. H. s. INDGE LAPPING MACHINE Filed May 14, 1936 2 Sheets-Sheet 2 .HERBEE'T SINDEE Patented June 15, 1937 UNITED STATES r creme LAPPING MACHINE tion of Massachusetts Application May 14, 1936, Serial No. 79,755

Claims.

This invention relates to lapping machines, and more particularly to an improved machine for simultaneously lapping plane surfaces on a plurality of work pieces.

One object of this invention is to provide a simple and thoroughly practical lapping machine for simultaneously lapping a plane face on a plurality of work pieces. A further object of this invention is to provide a lapping machine with a plurality of members which serve to yieldably hold a plurality of work pieces in operative engagement with the lap.

A further object of this invention is to provide i. a readily accessible means for loading and un- 15 loading a portion of the work carrying cage while the lapping operation continues on work pieces in the remainder of the cage. A further object of this invention is to provide an indexing mechanism for the cage member which enables indexing the cage to permit the same to be readily loaded from an operating station in front of the machine. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements. and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings in which is shown one of various possible embodiments of the mechanical. features of this invention,

Figure l is a vertical sectional view, taken through the improved lapping maclnne, having parts shown in elevation;

Figure 2 is a fragmentary plan View of the machine, showing the arrangement of the work holding devices and the work cage;

Figure 3 is a fragmentary cross sectional view, on an enlarged scale, taken approximately on the line 3-3 of Fig. 2, showing the details of the lap, the cage and the work holding mechanism; and

Figure 4 is a fragmentary cross sectional view, on an enlarged scale, taken approximately on the line 4-4 of Fig. 1, showing the details of the onerevolution clutch.

A lapping machine has been illustrated in the drawings comprising a base ll! which supports a rotatable lapping wheel H. The rotatable lapping wheel ii is mounted on a'fianged member 12 which is keyed to a sleeve l3. The sleeve i3 is rotatably supported in bearings l4 and i5 in the base Ill.

A driving mechanism is provided for rotating the lapping wheel I l at the desired lapping speed. This mechanism may comprise an electric motor 16 mounted on the base ill. The motor carries a gear I! mounted on the outer end of a motor shaft E8. The gear l'l meshes with a gear '59 mounted on the outer end of a rotatable shaft 20 which is journaled in a bearing H in the base A worm 22 is mounted on the inner end of the shaft 29 and meshes with a worm gear 23 which is keyed to the sleeve 53. When the motor is rotated, its rotary motion is transmitted through the shaft E8, the gear ll, the gear 59, the shaft 29, the worm 22, the worm gear 23, the sleeve l3, the flanged member l2, to rotate the lapping wheel H at the desired lapping speed.

A work holding cage 39 is provided for holding a plurality of work pieces iii in engagement with the operative face of the lapping wheel H for a lapping operation. The cage 39 is arranged for movement relative to the rotatable lapping wheel and is preferably arranged for a reciprocatory motion relative to the lapping wheel ii to carry the work pieces across the face of the lapping wheel during rotation thereof. A plurality of spaced guide pins 35 are supported in brackets 36 on a pan-shaped member 3'5. As illustrated in the drawings, four pins 35 are provided which are spaced at 90 from each other. The guiding pins 35 are adjustably supported on the brackets 35 and are held in adjusted position thereon by a screw 62. The cage member 3c is provided with a plurality of elongated slots 38 which cooperate with the pins 35 to guide the cage 30 during its reciprocatory movement. These elongated slots 38 are arranged parallel to each other and serve to hold the cage 3% against rotation while it is reciprocated across the face of the lapping wheel ll. Each of the studs 35 is provided with a fixed flange 39 which serves as a support for the lap" ping plate 33. Each of the studs 35 is also provided with a removable collar til and a nut M which serve to hold the cage in the desired operating relation with the supporting flanges 38.

In order to produce the desired reciprocatory motion of the cage 3i! during a lapping operation, a crank movement may be provided comprising a crankpin 5!] which is provided with an enlarged head 5|. The enlarged head 5! rides in an elongated slot '52 in the center portion of the cage 3d. The elongated slot 52 is arranged at substantially right angles to the elongated. slots 33 so vthat when the crankpin 58 is revolved, the enlarged head 5i sliding in the elongated slot 52 causes the cage member (iii to reciprocate relative to the rotating lapping wheel ii.

A suitable driving mechanism is provided for rotating the crankpin as at the desired speed to cause the required reciprocation of the cage 3! The crankpin is supported on a bracket 53 which is adjustably mounted on a rotatable head 54. The head 54 is keyed. to a shaft 55 which is rotatably supported in bearings 55 and 51. The bearings 56 and 51 are formed within the rotatable sleeve I3. The crankpin is preferably revolved at a slightly slower speed than the rotation of the lap 39. A slow speed drive is provided for the cage reciprocating mechanismso that the work pieceswill be reciprocated slowly across the operative face ofthe rotatable lapping' wheel. In the preferred construction, 'a gear 59 is keyed tothe lower end of the rotatable sleeve I3. The gear 60 meshes with a gearfil which is rotatably mounted on a stud 62. A gear 63 is keyed to rotate with the gear BI and meshes with a large'gear 64 mounted on the.lower end of the rotatable shaft 55. When the motor I6 is rotated to drive the worm gear 23'and cause a rotation of the lapping wheel II, the rotation of the sleeve I3 serves through the gear 69, the gear BI, the gear 63, and the gear 64, to rotate the shaft 55 and-the head 54 to revolve the crankpin 50. 7 During this movement, the enlarged head 5! slides within the elongated slot 52 and produces a reciprocatory movement of the work carrying cage 30.

7 It isdesirable to provide a suitable work holding device so that the work pieces may be. held in operative lapping contact with the lapping wheel I I at a desired and predetermined pressure. It isalso desirable to provide apluralityof loading stations for the cage in which a plurality of work pieces may be loaded into the cage or unloaded therefrom while the lapping operation on theremaining pieces continues, that is, to permit loading one section of the cage after a predetermined lapping operation has been performed on a plurality of work pieces whilethe 'machine continues in operation, lapping a plurality of other pieces of work. This mechanism may comprise a plurality of work holding plates 10 which are preferably pivotally mounted by means of pivot pins H to a central portion 12 which is fixed to the cage 30. The work holding plates 19 are each provided with-a plurality of' spring pressed plungers 15 which are. slidably supported in bushings 16 on the plate 10. The

plungers15 are provided with enlarged heads 11 which are arranged to engage the upper surface of the work piece.

" bushin 16 and the head 11. The spring-pressed A spring 83 serves to rock the latch BI into the plunge s are arranged to apply a desired pressureat the central portion of the workpiece to be lapped. Each of the work holding plates 10: is provided with an actuating handle and may be held in anoperating position to hold the work pieces in operative relation with the lap it by means ofa latch BI which is pivotally mounted on a stud 82 carried by the cage 30.

plate 10 and the handle 80 may-then be raised,

to rock the plate 10.about its pivot pin 1I so that the work pieces 3I may be readily removed from the aperture within the cage 30. Each of V. the work holding plates 10 is provided with an operating handle 80 and a latch 8| so that each plate may be individually released or latched in an operating positions By providing a construction of this type, a plurality of work pieces may be removed from the machine while the machine is operating and lapping the remaining pieces of A spring 18' surrounds the plungers'15 and is interposed between the.

work held by the cage 30, thereby permitting re moval of finish lapped pieces of work and inserting new pieces to be lapped while the machine is in continuous operation. 7

To facilitate loading and unloading of work pieces from the lapping machine, it is desirable to provide a suitable mechanism for indexing the cage member 30 so that the various sections of the cage may be readily unloaded and loaded from a single. operating station in front of the machine. To accomplish this result, the panshaped member 31 is preferably rotatably supported on the base I0. The base I0 is provided with a track 85 having a plurality of rollers 86 mounted therein and which serve as an antifriction bearing for the pan-shaped member- 31. An annular ring-shaped member 81 is fixedly mounted on the under side of the pan 31' and has. a projecting fiange'88 which engages the under side of the track 85 and serves as a guide to prevent lifting of the pan-shaped member 31.

The annular ring 88 is provided witha beveled gear 89 at its lower surface which meshes with a bevel gear 90 carried by a rotatable shaft 9| which is supported in a bearing 92 in a frame 94. A driving-motor 93 is supported on the frame 94 and is provided with a, pulley 95 which drives a pulley 96 by means of abelt 91. The pulley 96 is supported on one end of a rotatable shaft 98. A one-revolution clutch 99 is interposedbetween the shaft 9! and the shaft 98. This clutch may be actuated by means of av lever I00. The gear ratio between the gears 89 and 90 and the drive between the electric motor 93 and the shaft 98 are such that when the control lever I00 is moved to engage the one-revolution clutch 99, the pan 31 and the cage 30 will be indexed one station to bring the operatinghandle 80 into a position for unloading finish lapped pieces of work and replacing them with new pieces to be lapped without the necessity of stopping the rotation of the lap or the movement of the work carrying cage.

The one-revolution clutch is of a standard well known type, s'uch as thatknown as the Conway one revolution clutch. This clutch-may com prise a cylindrical member IOI which is keyed to the shaft Stand is surrounded by a band I02 which is-connected by a flange I03 with an integrally formed sleeve I04 which is rotatably supported on the shaft 9|. The lever I00'is formed integral with a cam member I05. A'

lever I05 is pivotally mounted on the band I02 and serves when rocked in a counterclockwise direction (Fig. 4) to tighten the band I02 on the member IOI and to thereby transmit motion from the motor 93 to the gear-90 to rotatethe.

gear 90 and the gear 89 to index thefcage 30 and pan 31 one station. The arm' I06 is pro-' vided with a rotatable roller I01 which rides on the cam. I05.

When the roller I01 is in the depressed portion of the cam, as illustrated in Fig. 4, the band I92 does not bind on thejsleeve -IOI and no motion is transmitted from the motor to the shaft SI 7 When the lever I0!) is rocked in a counterclockwise direction (Fig. 4), the cam I95 rotates and the roller I01 rides up onto the concentric portion of the cam I05; thereby rock ing the arm I05 in a counterclockwise direction; and servesto tighten the band I02 on the sleeve IOI to transmit power to the shaft 9|. is transmitted to the'shaft 9| until the roller I01 is revolved one complete revolution and again dropped into the depressed portion of the cam I05; thereby releasing the clutch band and stop Power ping the rotation of the cam 31 and the cage at the next loading and unloading station.

It is desirable to provide a suitable means for applying abradant material for a lapping operation. This mechanism may comprise an electric motor III] which serves to rotate a pump III contained within a reservoir H2. The reservoir H2 preferably contains a mixture of a lubricant and a fine abrasive or lapping powder. The pump I I I draws the fluid and abrasive from the reservoir H2 and forces it through a pipe Il3and through a nozzle I M to the lapping plate II.

It is desirable to stop the flow of abrading material during the lapping operation. This is preferably accomplished by providing a standard gate valve, such as a spring opened, trip closed valve H5 which may be automatically actuated by a stud I It, one of which is carried by each of the plates Ill, so that when the cage and pan are indexed to a new loading position, the valve H5 is automatically shut off to stop the flow of abradant fluid.

A suitable means is provided for agitating the fluid and abrasive so that the fluid passing through the pump contains a substantially uniform quantity of abrasive. This is preferably accomplished by providing a by-pass pipe II! which by-passes a portion of the fluid and abrasive from the pump I l I and forces it out through holes H8 in a pipe adjacent to the bottom of the reservoir H2. Fluid under pressure passing through the holes I 18 serves to continuously agitate the fluid and abrasive during the lapping operation to obtain a more or less uniform distribution of the abrasive within the lubricant.

While in the drawings the work cage has been illustrated as being supplied with apertures of a uniform size to lap the same size work piece, it is readily apparent from the foregoing disclosure that, if desired, a plurality of varying sizes and shapes of work pieces may be simultaneously lapped, if desired. It is only necessary to provide cage apertures of the desired shape and size to accommodate the work pieces to be lapped.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:-

1. A lapping machine comprising a rotatable lapping wheel having a plane operative surface, means to rotate said lapping wheel, a work cage arranged simultaneously to hold a plurality of work pieces in operative relation with said lapping wheel, means to move said cage relative to said wheel during the lapping operation, and means to index said cage to facilitate loading of the same without stopping the movement of the cage or the rotation of the lapping wheel.

2. A lapping machine comprising a rotatable lapping wheel having a plane operative face, means to rotate said lapping wheel, a work carrying cage, a plurality of work receiving apertures therein arranged simultaneously to hold a plurality of work pieces in operative relation with said lapping wheel, means to cause a relative movement between the cage and rotatable lapping wheel, and means including an indexing mechanism to index the cage through a partial rotation to facilitate loading of the same without stopping the lapping operation.

3. A lapping machine comprising a rotatable lapping wheel having a plane operative face, means to rotate said lapping wheel, a work cage, a plurality of work receiving apertures therein arranged simultaneously to hold a plurality of work pieces in operative relation with said lapping wheel, means to reciprocate said cage to carry the work pieces across the face of the lapping wheel, and means to index said cage to facilitate loading of the same without stopping the reciprocation of the cage or the rotation of the lapping wheel.

4. A lapping machine comprising a rotatable lapping wheel having a plane operative face, means to rotate said lapping wheel, a work carrying cage, a plurality of work receiving apertures therein arranged simultaneously to hold a plurality of work pieces in operative relation with said lapping wheel, said apertures being arranged in spaced groups, means to reciprocate said cage to carry the work pieces across the operative face of the lapping wheel, means including a power driven indexing mechanism intermittently to index said cage through a partial rotation to move groups of apertures successively to a load-' ing position without stopping either the movement of the cage or the lapping wheel.

5. A lapping machine comprising a rotatable lapping wheel having a plane operative face, means to rotate said lapping wheel, a work cage, a plurality of work receiving apertures therein arranged to hold a plurality of work pieces in simultaneous lapping engagement with said wheel, said apertures being arranged in groups, means to reciprocate said cage to carry the work pieces across the face of said lapping wheel, means to yieldably hold said work pieces in operative engagement with said lapping wheel, and an indexing mechanism operatively connected intermittently to index said cage to move groups of apertures successively to a loading position and thereby facilitate removal and insertion of work pieces before and after a lapping operation.

6. A lapping machine for simultaneously lapping a surface on a plurality of work pieces comprising a rotatable lapping wheel having a plane operative face, means to rotate said lapping wheel, a work carrying cage, a plurality of spaced apertures therein arranged to hold a plurality of work pieces simultaneously in operative relation with said lapping wheel, said apertures being arranged in spaced groups, means to reciprocate said cage to carry the work pieces across the lapping wheel, and means including a power driven manually controlled indexing mechanism to intermittently index said cage to facilitate loading portions of the cage without stopping the lapping operation on parts located in other portions of said cage. 7

7. A lapping machine comprising a rotatable lapping wheel, means to rotate said lapping wheel, a work carrying cage, a plurality of work receiving apertures therein arranged to hold a plurality of work pieces in operative relation with said lapping wheel, said apertures being arranged in spaced groups, means including a plurality of independent work holding plates carried by said cage each arranged to hold a group of said work pieces in engagement with said lapping surface, and means including a latch to independently hold said plates in an operating position.

8. A lapping machine comprising a rotatablelapping wheel, means to rotate said wheel, a work carrying cage, a plurality of work receiving apertures therein arranged to hold a plurality of work pieces in operative relation with said lapping wheel, said apertures being arranged in spaced groups, means to cause a relative movement between the cage and the rotatable lapping wheel, a plurality of independent work holding plates carried by said'cageand each arranged to hold a group of said Work pieces in engageing a plurality of pivotally mounted pressure ment with said'lapping surface under a predetermined pressure, and 111831151130 independently latch or release said-plates-in an operating position.

9. A lapping machine comprising a rotatable lapping wheel, means to rotate said Wheel, a

work carrying cage arranged to hold a plurality of work pieces in operative relation with said lapping'wheel, means tov cause a relative movement between the cage and the rotatable lapping wheel, a plurality of independent work holding DIHtESzCfiJI'lGd by said cage and arranged to hold a plurality of said ,work pieces in engagement with said lapping surface under a predeter mined pressure, means to independently latch or release said plates in an operating position, and means including an indexing mechanism intermittently to index the cage through a partial rotation to facilitate loading of the same with-' out stopping the lapping operation.

10. A lapping machine comprising arotatable lapping wheel, means to rotate saidlapping wheel, a work carrying-cage, a plurality of work receiving apertures therein arranged to'hold a plurality of, work pieces simultaneously in operative relation with said lapping wheel, said apertures being arranged in spaced groups on said cage, means to reciprocate said cage relative to-said rotatable lapping wheel, means to hold said cage in a, predetermined spaced relationship with said lapping wheel, means includplates carried by said cage, and'means to latch said plates in an'operatingposition, each plate being arranged to'simultaneously hold a group of work pieces in operative; relation with the lapping wheel for a lapping operation.

.11. A lapping machine comprising a rotatable lapping .wheel, means to rotate said lapping wheel, a work carrying cage, a plurality of work receiving apertures therein arranged to hold a plurality of work pieces in operative relation with said lapping wheel, said apertures being arranged in spaced groups on said cage, means to cause a relative movement' between the cage and rotatable lapping wheel, means to hold said cage in. a predetermined spaced relationship with said lapping wheel, means including a pluralityof pivotally mounted pressureplates carried by relation with said lapping wheel, said apertures being arranged-in spaced groupson said cage,"

means' to cause a relativemovement between the cage and rotatable lapping wheel, means tohold said cage in a predetermined spaced relationship with said lapping wheel, means includ--' ing; a plurality of pivotally mounted pressure plates'carried by said cage and arranged to be latched inan operating position to simultaneously hold a group of work pieces in operative relation with the lapping-wheel for a lapping operation, and means including a power driven onerevolution clutch intermittently to index the cage'through a partial rotation to facilitate loadingofthe samewithout'stopping of the lapping operation.

13. A lapping machine comprising a rotatable I lapping wheel, means to rotate said lapping wheel, a work carrying cage, a pluralityof work receiving apertures therein ,to hold a plurality of work pieces simultaneously in operative relation with said lapping wheel, said apertures being arranged in spaced groups, means to guide said cage for a reciprocatory movement rela-' tive to said lapping wheel, means to reciprocate said cage relativeto the rotatable lapping wheel,

a pluralityof independently movable work hold:

ing platesrcarried by said cage, each being arranged to independently hold a plurality of work pieces. in operative relation; with the lapping wheel, and means including a power driven indexing mechanism to index the. cage through a partialrotation to facilitate loading of the same at'a single operating the lapping operation. V V c 14. A lapping machine comprising arotatable station without stopping iapping'wheel, means to rotate said lapping:

wheel, a work carrying cage, a plurality of work receiving apertures therein to hold a plurality of work pieces" simultaneously in operative relation with said lapping wheel, said apertures being arranged in spaced groups, means including a plurality of elongated slots and pins to guide said cage fora reciprocatory movement relative to said lapping wheel, means to positively reciprocate said cage, adustable means to hold said cage in spaced relationship with the operative .sur-

face ofv said lap, and means to index said cage through a partial rotation to facilitate loading of the same, without stopping the lapping operation. T V

,15. A lapping machine comprising a; rotatable lapping wheel, means to rotate said lapping wheel, a work carrying cage, a plurality of work' receivingapertures therein to hold a plurality of work pieces simultaneously in operative relation with said lapping wheel, said apertures being arranged in spacedgroups, a pluralityof in-:

dependent pivotally mounted work holding plates each arranged to yieldably maintain a group of work pieces in operative relation with the lapping wheel, adustable means to hold saidv cage in spaced relationship with the operative face of the lapping wheel, means to guide said cage for a reciprocatory movement relative tothe lapping wheel, means to reciprocate said cage, and means including a manually operable one revolution clutch to index said cage to bring successive work holding plates into a loading position to facilitate loading of the cage without ping operation.

stopping the lap- HERBERT S. INDGE; 

